Saturday, December 10, 2016

This movie, directed by Emily V. Driscoll, is
an award-winning short documentary that follows NYC sci-artist Mara G.
Haseltine as she creates a sculpture to reveal a microscopic threat
beneath the surface of the ocean.

During a Tara Oceans expedition to
study the health of the oceans, Haseltine finds an unsettling presence
in samples of plankton she collected.

The discovery inspires her to
create a sculpture that shows that the microscopic ocean world affects
all life on Earth.

The results are in, and while the world's oceans show no significant decline over the past year, their condition should not be mistaken as a clean bill of health.

So say the scientists behind the 2016 Ocean Health Index (OHI), an annual study that evaluates key aspects—biological, physical, economic and social—of ocean health worldwide.
The OHI defines a healthy ocean as one that sustainably delivers a range of benefits to people now and in the future based on 10 diverse public goals.
This year's score is 71, unchanged from those for 2013-2015, which were recalculated using the current year's improved methods.
"We've given the oceans their annual checkup and the results are mixed," said UC Santa Barbara ecologist Ben Halpern, OHI chief scientist.
"It's as if you went to the doctor and heard that, although you don't have a terminal disease, you really need to change your diet, exercise a lot more and get those precancerous skin lesions removed.
You're glad you're not going to die but you need to change your lifestyle."

Coastal protection

A score of 100 means optimal productivity from the ocean in a sustainable way.

Established in 2012, the OHI is a partnership between UCSB's National Center for Ecological Analysis and Synthesis (NCEAS) and the nonprofit environmental organization Conservation International.
The index serves as a comprehensive tool for understanding, tracking and communicating in a holistic way the status of the ocean's health.
It also provides a basis for identifying and promoting the most effective actions for improved ocean management on subnational, national, regional and global scales.
"What is really exciting about having several years of assessment is that we can start to see where and by how much scores are changing year to year and begin to understand the causes and consequences of those changes," said Halpern, director of NCEAS and a professor in UCSB's Bren School of Environmental Science & Management.

High seas

Scores for each goal—or subgoal—range from 0 to 100, and the fourth consecutive global score of 71 indicates that while the ocean has remained stable, its condition is far from the desired 100 that would indicate full sustainability.
Two exclusive economic zones (EEZs) demonstrate higher scores and therefore better efforts at sustainability.
For example, Germany, with a population of 81 million, ranked fourth among the 220 EEZs assessed with a score of 85.
The much-less-populated Seychelle Islands (with about 97,000 people) ranked eighth with a score of 84.
These areas exemplify effective social and environmental governance systems for improving ocean health.

Tourism & recreation

Successive years of global OHI assessments also identify potential trends.
The Livelihoods & Economies goal, for example, showed the most rapid score increase between 2012 and 2013, possibly reflecting recovery from the recession that began in 2008.
Lasting Special Places (a subgoal of Sense of Place) scores improved by an average of 0.5 points per year, likely due to the designation of marine protected areas.
Consistently low scores for Tourism & Recreation (47) highlight countries that are not sustainably maximizing benefits derived from a healthy tourism sector.
Scores for Food Provision (54) and Natural Products (48) indicate that many regions are either harvesting unsustainably or not maximizing their sustainable potential to produce more food from the sea.

High Seas: Food Provision: Wild Caught Fisheries

The overarching issue of poor quality data (or no data at all) limits the ability to estimate the status of fish stocks in many regions as well as the overall status of fisheries.
Biodiversity (91) and Coastal Protection (87) goals remain the highest scoring.
Reference points for both include maintaining coastal habitats at or about their 1980 levels, so decline of these scores from 100 has occurred in less than four decades.
Continuing threats to habitat could lower scores further.

Clean waters

The OHI team works directly with more than 25 countries across priority marine regions, including the Pacific, East Africa and Southeast Asia.
Nations in these areas lead independent assessments known as the OHI+, which have already driven marine conservation actions at national levels by shaping China's 13th five-year plan, Ecuador's National Plan for Good Living and Mexico's National Policy on Seas and Coasts.
By providing an annual comprehensive database baseline for global ocean health, the OHI offers all coastal countries a starting place for assessing the status of their marine resources and environments and utilizing an ecosystem-based approach toward management.
"We believe the Ocean Health Index gives reason for hope by providing a detailed diagnosis of the state of ocean health and also a framework that allows countries to identify and prioritize the most necessary resilience actions to improve ocean health," said Johanna Polsenberg, senior director of governance and policy for Conservation International's Center for Oceans.
"This is where our work is most valuable. It may take some time for such actions to be reflected in the scores—but the steps being taken are essential to ensure a healthy ocean into the future."

Scientists surveying the seabed in areas affected by
last week’s earthquake have confirmed a 34km rupture in the offshore
continuation of the Kekerengu Fault, known as the Needles Fault.

NIWA’s flagship research vessel returned to port in Wellington today
after a two-week voyage, initially to undertake seismological research
on the Hikurangi subduction zone, off the North Island’s East Coast
which is regarded as New Zealand’s largest earthquake and tsunami
hazard.
However, with several leading marine geologists on board, it was
decided to divert the ship to take core samples and survey the seabed in
areas affected by the Mw 7.8 earthquake.

Hikurangi Trench on a Linz nautical chart (GeoGarage platform)

New mapping and profiling confirmed that the Needles Fault ruptured

Voyage leader and NIWA marine geologist Dr Philip Barnes said today
new mapping and profiling confirmed that the Needles Fault ruptured
forming newly discovered scarps on the seafloor along the Marlborough
coast south of Cape Campbell.
Dr Barnes said the length of the Kekerengu-Needles fault rupture may
now extend for about 70km – 36km on land and 34km under the sea.

New mapping and profiling confirmed that the Needles Fault ruptured
forming newly discovered scarps on the seafloor along the Marlborough
coast south of Cape Campbell. [NIWA]

61 sediment cores collected

Scientists collected 61 sediment cores, each about 5.5m long from
sites on the continental margin between the Kaikoura coast and Poverty
Bay that will provide evidence of submarine landslides.

3D visual of the Kaikoura Canyon's submarine topography

courtesy of NZHerald

The cores revealed the earthquake generated a huge turbidity current
in the Hikurangi Trough, offshore from Marlborough and Wairarapa.
A
turbidity current is a rapidly moving underwater current comprising mud,
sand, gravel and water.
It eventually results in layers of sediment
being deposited across the sea floor.
These are known as turbidites.
“We detected a very recent turbidite about 10-20cm thick over a very
large region, extending at least 300km from Kaikoura. It is still
settling on the seabed from the water column and may not complete this
process for some time,” Dr Barnes said.
The precise location of the underwater landslides that generated the turbidity current has not been studied.
Data collected over the past few days will help inform understanding
of the entire fault network activated during the earthquake.

Earthquake presents opportunity to undertake new science and make discoveries

Dr Barnes said last week’s earthquake presented a rare opportunity to study how an area has been affected in real time.
“It is an exciting opportunity to undertake new science and make
discoveries that will contribute to the understanding to New Zealand’s
fault network and what changes when there is an earthquake,.”
The voyage was funded by the Ministry of Business, Innovation and
Employment as part of a five-year programme to address critical gaps in
understanding about the earthquake potential of the Hikurangi subduction
zone.

This simulation shows how the seismic waves of the magnitude 7.8 earthquake were propagated across New Zealand.

Subduction zones produce the planet’s deadliest earthquakes and
tsunamis – such as the 2011 magnitude 9 earthquake in northern Japan and
the M9.3 earthquake in Sumatra in 2004.
These are known as “megathrust
earthquakes”.
The aim is to advance knowledge of the earthquake potential on the
Hikurangi margin, to more reliably forecast the hazard it poses to New
Zealand.
The research involves scientists from NIWA, GNS Science, the
universities of Auckland, Otago, Canterbury and Victoria as well as
scientists from France, Turkey, Japan and the US.

Wednesday, December 7, 2016

The Japanese mini submarine HA-19 (similar to the mini sub sunk by the USS Ward),

which washed ashore on December 8, 1941

Photo courtesy of Naval History and Heritage Command

On December 7, 2016, 75 years after the attack on Pearl Harbor, join
us for a live dive on two Japanese mini submarines, the first of which
was sunk by the USS Ward prior to the attack.
This will be the
first time the public will be able to view live underwater exploration
of the submarines in real time.

A remotely operated vehicle deployed
off of the NOAA Ship Okeanos Explorer will send back images of the wreck site.
James Delgado, director of maritime heritage, NOAA Office of National
Marine Sanctuaries and Frank Cantelas, marine archaeologist, NOAA
Office of Ocean Exploration and Research will be on board, describing
the exploration.
"Until now, only a handful of explorers and scientists have seen
these relics of the war in the deep sea," notes James Delgado, "but
thanks to technology, anyone and everyone can now dive with us in the
first live exploration of the 'midget' submarines that represent the
beginning of the war in the Pacific."
The research team will be using a remotely operated vehicle from NOAA Ship Okeanos Explorer to revisit the historic wreck site and document its condition.
The dive will be live-streamedand the public is invited to participate.

The conning tower of the mini submarine sunk by the USS Ward.

Photo: University of Hawaiʻi/HURL

On the morning of December 7, 1941, U.S. naval vessels and
aircraft on patrol outside Pearl Harbor spotted a partially submerged
submarine trying to enter the harbor, but alerts were not immediately
sent.
Ninety minutes before Pearl Harbor was bombed by air, the
destroyer USS Ward fired on the mini submarine, sinking the
sub.
The event marks the first U.S. shots fired and the country's entry
into World War II in the Pacific.
The NOAA team will dive on the wreck
of this submarine.
The second submarine to be explored during the dive disappeared
on the morning of December 7, 1941.
It was discovered in shallow waters
in 1951, raised by the U.S. Navy, and taken out to sea to be dumped in
deeper water.
In 1992, the University of Hawaiʻi's Undersea Research
Laboratory rediscovered it.
It has been periodically visited by the
university's submersibles, the last time in 2013.

On a planet mostly covered by water, there is plenty of dull, dirty
and dangerous work to be done at sea, but robotics provides breakthrough
capabilities that will transform how humans interact with the ocean.
New technical capabilities and increasing market demand have converged
to kick off an era of growth in autonomous, unmanned systems—an
important component of the blue economy’s infrastructure.
Picture a small ocean robot swimming deep beneath the sea.
It could
be searching, mapping, servicing equipment, or performing any number of
other activities that we take for granted while living on the 28% of the
planet that is not covered in water.
This robot works in a
hostile environment.
Saltwater can short-circuit electronics and corrode
metal, and deep under the ocean, water exerts a crushing pressure of
tonnes per square inch.
Closer to the surface, there are waves, wind and
extreme weather.
Sharks bite things to see if they’re edible, and algae
and barnacles grow wherever they can, fouling mechanisms and sensors.
The field of ocean robotics is decades old and, thanks to steady
development and funding from organisations like the United States Office
of Naval Research and oceanographic research labs around the world,
many of the challenges it presents now have solutions.
Energy,
communications and market development have all been holding back the
widespread adoption of ocean robotics.
Fortunately, there’s now good
news on all these fronts.

The SHARC unmanned surface vehicle detected, reported, and tracked a manned submarine during the Unmanned Warrior exercise off the coast of Scotland in October 2016.

Energy is the key to autonomy

Robotic autonomy isn’t just about artificial intelligence.
For ocean
systems, energy is the first constraint on how independent a robot can
be.
The most common robotic systems in the marine industry are remotely
operated vehicles (ROVs) that are powered through a tether connected to a
ship.
Famously, several ROVs were deployed a mile deep to stop the oil
gushing from the ocean floor after the catastrophic failure of the
Deepwater Horizon rig.
These ROVs, while often extremely sophisticated,
are an extension of highly trained human crews living and working on
specialised ships.
Since ship operations are expensive, ship-based robot
operations are even more expensive.
Unmanned underwater vehicles (UUVs) achieve great agility and
flexibility by eliminating the ROV’s tether, cutting the cord to the
support ship.
But this means that UUVs must rely purely on stored
energy; their limited battery capacity constrains their range and the
power available for sensors.
Most UUVs are deployed from ships and
operated in a similar way to ROVs.
Improved battery technology, combined with low-power sensors and
processors, is leading to rapid advances in the efficacy of long-range
UUVs.
Buoyancy gliders, a type of UUV, use hyper-efficient propulsion to
spend months at sea and operate in a way that is truly unmanned—with no
ship in sight.
At the surface of the ocean, a newer class of autonomous ocean
vehicles called unmanned surface vehicles (USVs) has emerged.
Harvesting
energy from wind, waves and the sun, USVs such as Liquid Robotics’ Wave
Gliders convert natural energy to power propulsion, sensor payloads and
communication devices.

Boeing’s latest unmanned undersea vehicle (UUV) Echo Voyager.

The 51-foot-long vehicle is the latest innovation in Boeing’s UUV family, joining the 32-foot Echo Seeker and the 18-foot Echo Ranger.

Robots are teaming up

The communications network for ocean robots is comprised of ocean robots, which are now being deployed in teams above, below and on the surface of the ocean.
Radio waves and light don’t propagate through the ocean like they do
through the atmosphere.
Just a few centimetres of saltwater is enough to
block radio and GPS signals.
Sound, on the other hand, travels enormous
distances underwater.
Robots at the surface, equipped with acoustic
modems and satellite links, are being used to extend communications and
positioning services to a wide variety of subsea devices, including
sea-floor sensors and UUVs.
In combined deployments, aerial drones with optical sensors and
surface robots with acoustic sensors co-operate to extend communication
ranges and provide a persistent and agile monitoring system.
A
system-of-systems approach enables real-time, actionable updates for
early detection, warning and monitoring.

Paint the Target (Liquid Robotics promotional video)

Networked robots aren’t just a product: they’re a platform

This network of robots will become more capable and valuable as it
grows.
Economies of scale mean that the more robots you build, the less
each one costs.
Without the need for fuel and human labour, operating
costs can be very low.
Reliability also improves with numbers, for each
individual robot but also as the result of deploying slightly more
robots than are necessary to complete a job.
All this leads to a
virtuous cycle of expanding utility and reduced costs as adoption grows.
The network effect also applies to a growing, global ecosystem of
sensor developers, platform manufacturers and integrators who provide
creative solutions to diverse market needs in security, offshore
industry, science and environmental assessment.
Today, ocean robotics
are in the same position as the iPhone was when Apple created it as a
platform on which others would innovate and build—applications are at a
nascent stage.
This is changing as the underlying technology gains
greater capabilities and is produced in greater volume.
It’s an exciting
time that will see a new industry of ocean application developers
emerge.

The digital ocean will underpin the blue economy

Imagine an ocean where networks of sensors, manned and unmanned
systems, and satellites are connected to give us instant, affordable
access to information.
This is the vision for the digital ocean.
It’s
not science fiction: it’s a prerequisite for more-effective ocean
preservation and economic expansion for the blue economy.
The networked ocean will deliver real-time seismic warnings and more
accurate hurricane and cyclone forecasts that will help save lives and
economies.
It will help expose illegal, unregulated and unreported
fishing (IUU), and trafficking in drugs and people.
Robots already help
research, measure, and monitor precious marine ecologies.
In the digital
ocean, the insights we gain will foster new scientific discoveries, new
job opportunities and new economic growth.
In science fiction, robots don’t run out of power and can communicate
from seemingly anywhere.
In reality, powering devices and networking
their data takes a lot of effort.
But as these issues are addressed and
the market matures, the opportunity for autonomous ocean devices is
enormous.
Ocean robotics is at an inflection point where it is ready to
enable a safer, sustainable digital ocean.

Monday, December 5, 2016

We asked yesterday if the pull of
gravity is the same everywhere on Earth. As many of you noted, the
answer is no.

This map of Earth's gravity field, based on airborne and
satellite measurements, depicts variations in Earth's gravity field.

As
Astronomy Picture of the Day explained when they ran a similar image in
2014: "High areas on this map, colored red, indicate areas where gravity
is slightly stronger than usual, while in blue areas gravity is slightly
weaker.

Many bumps and valleys can be attributed to surface features,
such as the North Mid-Atlantic Ridge and the Himalayan Mountains, but
others cannot, and so might relate to unusually high or low sub-surface
densities."

In addition, processes happening deep in the Earth's
mantle—such as descending tectonic plates and hot mantle plumes—can also
affect the strength of the gravitational field.

The geoid is a measurement of mean sea level (MSL).
When you average
out the motion of waves, the level at which water settles is MSL.
To calculate MSL, all you have to do is just measure the average level of the oceans… and there you have it.
But how about on land?
Let’s say you dig a canal away from the ocean inwards to the land.
The level the water would settle could be interpreted as mean sea level.
The geoid is the hypothetical MSL without digging a canal…
And it’s
used by surveyors to measure precise surface elevations as a true zero
surface in a vertical datum.

Distance to the center of the Earth

Defy Your Notion of Gravity with the Geoid

All objects on Earth fall at 9.81 m/s2 (meters, per second, per second).
Actually, no they don’t.
Gravity differs where you are on Earth, as shown in the geoid model.
For example, mountains have more mass than valleys.
As a result, gravity at the Rocky Mountains is relatively stronger to other locations on Earth.
Gravity on the Earth’s surface ranges from 9.7639 m/s2 in Peru to 9.8337 m/s2 in the Arctic.

This also means that our planet is actually very bumpy and non-uniform.
It’s not a sphere.
It’s not as smooth that most people tend to think it is.

Data courtesy of NASA’s GRACE Gravity Model

Other effects on gravity are because:

The Earth bulges at the equator from rotational forces. This
means the difference from the center of the Earth and the surface is
smaller at the poles than at the equator.

The material composition of the Earth varies and matter isn’t evenly
distributed, which adds more complexity to understanding gravity.

Small Tugs and Pushes from a Pair of Satellites

How do you measure the geoid?
To measure mean sea level, you can use a tide gauge and average out the results over a long period of time:

Tidal Gauge | Image Credit: NOAA

But you’d need a lot of tide gauges placed around the entire globe.
So this is why satellites like NASA’s GRACE mission (Gravity Recovery and Climate Experiment) and ESA’s GOCE mission
(Gravity Field and Steady-State Ocean Circulation Explorer) are
measuring our planet’s gravity field with a precision never obtained
before.
How do these satellite missions do this?
GRACE is a pair of satellites in the same orbit
approximately 220 kilometers apart.
When the leading satellite increases
speed, this means there is a greater gravitational pull. If the leading
satellite slows down, this means there is less gravitational pull.
These tugs and pushes in gravity are measured using microwave pulses
from one satellite to the other. Each satellite position is being pinned
down with GPS.
The end result is the most accurate measurements of gravity anomaly to date.

Predicting Earthquakes from Subduction Events

Earth’s Interior– Scientists are closer than ever to earthquake prediction.
Because we can retrieve variations in the geoid, these subduction
events are like retrieving earthquake signatures.
Geoid variations were
associated with more than 98 per cent of the earthquakes of magnitude 9
or above, around 60 per cent for magnitude 8.8, 40 per cent for
magnitude 8.6 and 33 per cent for magnitude 8.3.

Understanding Ocean Circulation and Sea Level Change

Climate Change – Ocean circulation, tide gauges and sea level…If all the ice melted,
climate scientists would measure change by the Earth’s rising sea
levels and tide gauges.
GRACE measures mass change from the melt of
Arctic ice.
It helps us understand if ocean circulation is changing and
how if affects world climate change.

Wrapping Things Up

As you walk around Earth, you weigh a little more or less depending
on where you are.
It’s actually a function of how much mass is below
you.
The geoid derived from the GRACE and GOCE missions can sense just
how much that mass is.
We love remote sensing applications.
And the list goes on for these uniquely interesting satellite missions.
Earthquake prediction, climate change models and the water cycle are
some of the areas that the geoid is helping us understand how our Earth
works.
But the list of GRACE applications doesn’t stop here.